Heat-exchangers



Sept. 8, 1964 R. A. CHADBURN ETAL 3,147,799

HEAT-EXCHANGERS Filed April 14, 1960 2 Sheets-Sheet 1 INVENTORSRana/Lanna MLLlAMH-DIWA/E WuunnRZnmv A OR/VE) Sept. 8, 1964 Filed April14, 1960 R. A. CHADBURN ETAL 'HEAT-EXCHANGERS 2 Sheets-Sheet 2 INVENTORSRoun- Acmpmm WuunnH-D/v/Ms AND BY WILL/120R. Znmv United States Patent3,147,799 HEAT-EXCHANGERS Robert A. Chadburn and William H. Divine,Spring Garden Township, York County, and Willard R. Zahn, WestManchester Township, York County, Pa., assignors to Borg-WarnerCorporation, Chicago, Ill., a corporation of Illinois Filed Apr. 14,1960, Ser. No. 22,170 3 Claims. (Cl. 165-86) This invention relates toheat-exchangers and, more particularly, to heat-exchangers adapted forthe batch cooling or heating of liquids.

It is an object of the invention to provide a liquid heat-exchanger,including a plurality of banks of heatexchange tubes adapted forinsertion into a liquid to be heated or cooled, and wherein aheat-exchange fluid is passed in series flow through the various banks.Yet another object of the invention is to provide a heat-exchanger ofthe type just above-mentioned, wherein means are provided foroscillating the heat-exchange tubes to increase heat transfer.

A further object is to provide an oscillatable heatexchanger for batchcooling of liquid of minimum power requirements, easily cleaned, andwherein no Stratification of the liquid to be heated or cooled mayoccur.

The invention consists of the novel constructions, arrangements anddevices to be hereinafter described and claimed for carrying out theabove-stated objects and such other objects as will appear from thefollowing description of a preferred embodiment of the inventiondescribed with reference to the accompanying drawings, in which:

FIG. 1 is an elevation of a heat-exchanger assembly according to theinvention, with parts broken away to better show details;

FIG. 2 is a top view thereof;

FIG. 3 is a sectional view in elevation of the heat-exchanger;

FIG. 4 is a top view of the heat-exchanger, with parts thereof brokenaway in order to better show details;

FIG. 5 is an elevation of a typical spacer web used in conjunction withthe heat-exchanger;

FIG. 6 is an elevation of a typical heat-exchange tube for use with theheat-exchanger; and

FIG. 7 is a top view of of the heat-exchange tube of FIG. 6.

Like numerals refer to like parts throughout the several views.

Turning now to FIG. 1, a container 10 is provided for receiving theparticular substance to be cooled or heated. In this particularinstance, container 10 is of semi-spherical configuration, but it willbe apparent that it may take any particular shape as desired. Container10 is supported on four legs 11 (only two of which are shown). Legs 11terminate in typical casters 12, receiving Wheels 13 on which thecontainer 10 may be rolled. A plurality of bracing members 14 and 15 maybe provided between legs 11, as desired, in order to suitably strengthenthe entire structure.

A heat-exchanger 16 is mounted above container 10. Heat-exchanger 16 issupported for vertical movement both into and out of container 10, andat the same time is adapted for being oscillated within the container10. In order to mount heat-exchanger 16, four telescoping leg posts 17receive a machinery platform 18 at their upper ends thereof. A gussetplate 19 is optionally attached to the bottom of each leg post 17 forthe purpose of stabilizing the entire structure. Bracing members (notshown) may be attached between gusset plates 19 to add the necessaryrigidity.

3,147,799 Patented Sept. 8, 1964 Leg posts 17 are formed of a firstfixed leg portion 20 and a second movable portion 21. A gusset plate 22is mounted on top of each leg portion 21 for the purpose of suitablysecuring machinery platform 18 thereto. A drive screw nut 23 is fixedlyreceived on each fixed leg portion 20. Each drive screw nut 23 receiveswithin it a drive screw 24. Machinery platform 18 is supported on drivescrews 24, and is movable up wardly and downwardly therewith as thedrive screws are rotated within drive screw nuts 23.

A locking arm 25 has one end 26 thereof attached to fixed leg portion20, while the other end 27 thereof is attached to leg 11 of container 10in order to suitably secure and center the same with respect toheat-exchanger 16.

Some means must be provided to rotate drive screws 24, and this takesthe form of a drive screw motor 28, suitably mounted on machineryplatform 18. Motor 28 rotates a roller chain sprocket drive 29. Asprocket chain 30 is trained over four roller chain sprockets 31 andalso over sprocket drive 29. Roller chain sprockets 31 are each aflixedatop a respective drive screw 24 by any suitable means. A flanged thrustand radial bearing 32 is suitably affixed to machinery platform 18 andjournals drive screw 24 therein. Flanged bearing 32 additionally servesto support machinery platform 18 by way of a flange 33 on the drivescrews 24. A suitable switch 34 is provided on one of the movable legportions 21 in order to operate motor 28 for the purpose of drivingsprocket chain 30 to rotate the drive screws 24. It will be appreciatedthat suitable electrical connections (not shown) will be providedbetween switch 34 and motor 28.

Heat-exchanger 16 comprises a liquid plenum 35 formed of a top wall 36and a bottom wall 37, suitably joined together by a side wall 38. Bottomwall 37 has a plurality of apertures 39 therein, each aperture receivinga heat-exchange tube 40. Heat-exchange tubes 40 are closed at the bottomthereof by a suitable plug 41. It will be appreciated that the variousheat-exchange tubes 40 will be of varying length, depending on theconfiguration of the container 10. If container 10 were of rectangular,boxlike form, then all heat-exchange tubes 40 could be of the samelength. Heat-exchange tubes 40 are arranged into a plurality of banks 42for fluid flow purposes, with the tubes of one bank being offset withrespect to the tubes in the next adjacent bank (see FIG. 4) for purposesto be hereinafter explained. A plurality of spacer webs 43 are provided,each comprising a flow-directing member 44 seated between top wall 36and bottom wall 37, and a plurality of spacer members 45, each receivedwithin a corresponding heat-exchange tube 40. The spacer members 45divide each tube 40 into an inlet fluid flow passageway 46 and an outletfluid flow passageway 47. A single flow-directing member 48 is alsoprovided between top Wall 36 and bottom wall 37, and serves to separatea liquid inlet 49 to liquid plenum 35 from a liquid outlet 50.

Heat-exchanger 16 receives a hollow shaft 51 centrally thereof, and isfastened thereto as by welds 52. Hollow shaft 51 is internally threadedas at 53 to receive any one of a plurality of optional items, such as aremovable blade 54. It will be apparent that removable blade 54 may bereplaced by a screw member (not shown), or a paddle member (not shown),as optionally desired. Hollow shaft 51 terminates at the upper endthereof in a flange 55 secured thereto by any suitable means.

Means are provided for oscillating heat-exchanger 16 and takes the formof a flanged oscillating drive shaft 56. Drive shaft 56 is journaled ina flanged thrust and radial bearing member 57, attached to machineryplatform 18 by any suitable means. Bearing member 57 is similar tobearing member 32, in that it not only journals shaft 55, but alsoreceives a flange thereof (not shown) for supporting the same withrespect to machinery platform 18. Shaft 56 terminates at the lower endthereof in a flange 58, attached thereto by any suitable means. Flanges55 and 58 are bolted together by way of a plurality of bolts 59. Asecond bearing 60 is provided for journaling the extreme uppermostoscillating portion of drive shaft 56, and is supported on a bearingsupport structure 61, attached to machinery platform 18.

The means for oscillating drive shaft 56 take the form of a variablespeed drive motor 62, driving a speed reducer 63. Speed reducer 63drives an adjustable, oscillating drive 64. A first crank 65 has one endthereof connected to oscillating drive 64 by way of a bolt 66 forrotation therewith. The second end thereof is attached to a second crank67 by way of a bolt 68. Crank 67 has its other end suitably attached tooscillating drive shaft 56. A suitable switch 69 is provided on one ofthe movable leg portions 21 in order to operate motor 62. Suitableelectrical connections (not shown) are provided between switch 69 andmotor 62.

In operation, the material to be cooled or heated is placed withincontainer 10. Motor 28 is operated to rotate drive screws 24 in adirection to lower heat-exchanger 16 into container 10. Any suitablesource of chilled or heated heat-exchange fluid may be provided (notshown), and the fluid flows through inlet 49 into liquid plenum 35 andthence into a first bank of heat-exchange tubes 40. It will beappreciated from an inspection of FIG. 4 taken in conjunction with FIG.6 that the fluid flow will be into the inlet fluid passageway 46 of theheat-exchange tubes 40, thence under the spacer members 45, and up theoutlet fluid passageway 47 of the heat-exchange tubes 40, back into theplenum 35, and thence to the next bank of heat-exchange tubes. It willbe apparent that the above set out series flow will continue untilfinally the fluid will exit the plenum 35 by way of outlet 50. Thisseries flow of the heat-exchange fluid gives excellent velocities and,in addition, represents a cost saving with respect to material flow,pumping, power expended, etc. The alternative to series flow would be,of course, to provide for simultaneous flow through all theheat-exchange tubes.

Heat-exchanger 16 is preferably oscillated within container 10 toincrease the heat transfer between the tubes and the material to becooled or heated. It will be noted that the heat-exchange tubes 40 ofone bank 42 are offset with respect to the next adjacent bank, so thatno Stratification of the substance being cooled or heated withincontainer 10 may occur. This problem would, of course, only arise withrespect to fairly viscous substances. In order to oscillate theheat-exchanger 16, variable speed motor 62 is placed into operation,driving speed reducer 63 and oscillating drive 64. It will beappreciated from an inspection of FIG. 2, that rotation of oscillatingdrive 64 will have the effect of oscillating crank 67, attached driveshaft 56, and hollow shaft 51, which will then oscillate heat-exchanger16.

The minimum oscillation preferred is the distance between the variousbanks 42 of heat-exchange tubes 40 to overlap the banks. Again, thisrelates to the problem of Stratification when the substance being cooledor heated is a particularly viscous substance. The oval or ellipticalshape of the heat-exchange tubes 40, as shown, is preferred over a roundshape to give a larger surface area for the same volume whereby the heattransfer is increased. In addition, less power is needed to oscillatethe heat-exchanger 16 because of the greater slip flow across the majorpart of the tube surface. This greater slip flow also has the effect offurther increasing the heat transfer rate.

Vertical tubes 40 with smooth (rather than finned or otherwiseirregular) surfaces are desirable to produce low drag-out losses, eventhough the heat transfer may be somewhat less. In addition, cleaing ofthe tubes 40 by dipping or inverted spray is facilitated. Irregular orfinned tubes would produce ledges or blind spots to hinder theseprocesses.

We wish it to be understood that our invention is not to be limited tothe specific constructions and arrangements shown and described, exceptonly insofar as the claims may be so limited, as it will be apparent tothose skilled in the art that changes may be made without departing fromthe principles of the invention.

We claim:

1. A heat-exchanger comprising a heat-exchange fluid plenum, said plenumdefining a continuous cavity, a plurality of radially arranged banks ofspaced heat exchange tubes depending from and communicating with saidplenum, each bank including a plurality of tubes, the said tubes beingclosed at their ends remote from said plenum, spacer means within saidtubes of each bank dividing said tubes into inlet and outlet fluid flowpassageways, a plurality of fluid flow directing means in said plenumsegregating the outlet passageways of one bank of tubes and the inletpassageways of the next adjacent bank of tubes, said spacer means andsaid fluid flow directing means of each bank being integral, wherebyseries fluid flow through said banks of tubes and parallel flow throughthe tubes in each of said banks is effected, and an external fluid inletcommunicating with the inlet passageways of one bank of tubes, anexternal fluid outlet communicating with the outlet passageways of thenext preceding bank of tubes and a baffle member within said plenumencompassing the inlet passageways of one of said banks of tubes andseparating said external fluid inlet and outlet.

2. The heat-exchanger of claim 1 including means for oscillating saidheat-exchange tubes, whereby the tubes will effect a greater heatexchange between themselves and a fluid in a vat in which the tubes areadapted to be positioned.

3. The heat-exchanger of claim 1 including means for vertically movingsaid heat-exchange tubes, whereby said tubes may be moved into and outof a fluid in a vat in which the tubes are adapted to be positioned.

ReferencesCited in the file of this patent UNITED STATES PATENTS 599,047Rider Feb. 15, 1898 1,251,894 Kitton Ian. 1, 1918 1,458,321 Bowman June12, 1923 1,740,192 McNeil Dec. 17, 1929 1,829,753 MacLean Nov. 3, 19311,948,280 Schildman Feb. 20, 1934 2,295,098 Cornell Sept. 8, 19422,637,538 Boutros et al. May 5, 1953 2,991,982 Johnson July 11, 1961FOREIGN PATENTS 173,827 Great Britain Jan. 19, 1922

1. A HEAT-EXCHANGER COMPRISING A HEAT-EXCHANGE FLUID PLENUM, SAID PLENUMDEFINING A CONTINUOUS CAVITY, A PLURALITY OF RADIALLY ARRANGED BANKS OFSPACED HEAT EXCHANGE TUBES DEPENDING FROM AND COMMUNICATING WITH SAIDPLENUM, EACH BANK INCLUDING A PLURALITY OF TUBES, THE SAID TUBES BEINGCLOSED AT THEIR ENDS REMOTE FROM SAID PLENUM, SPACER MEANS WITHIN SAIDTUBES OF EACH BANK DIVIDING SAID TUBES INTO INLET AND OUTLET FLUID FLOWPASSAGEWAYS, A PLURALITY OF FLUID FLOW DIRECTING MEANS IN SAID PLENUMSEGREGATING THE OUTLET PASSAGEWAYS OF ONE BANK OF TUBES AND THE INLETPASSAGEWAYS OF THE NEXT ADJACENT BANK OF TUBES, SAID SPACER MEANS ANDSAID FLUID FLOW DIRECTING MEANS OF EACH BANK BEING INTEGRAL, WHEREBYSERIES FLUID FLOW THROUGH SAID BANKS OF TUBES AND PARALLEL FLOW THROUGHTHE TUBES IN EACH OF SAID BANKS IS EFFECTED, AND AN EXTERNAL FLUID INLETCOMMUNICATING WITH THE INLET PASSAGEWAYS OF ONE BANK OF TUBES, ANEXTERNAL FLUID OUTLET COMMUNICATING WITH THE OUTLET PASSAGEWAYS OF THENEXT PRECEDING BANK OF TUBES AND A BAFFLE MEMBER WITHIN SAID PLENUMENCOMPASSING THE INLET PASSAGEWAYS OF ONE OF SAID BANKS OF TUBES ANDSEPARATING SAID EXTERNAL FLUID INLET AND OUTLET.